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<b>DbEnv::set_lg_dir</b>
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<b><pre>
#include &lt;db_cxx.h&gt;
<p>
int
DbEnv::set_lg_dir(const char *dir);
<p>
int
DbEnv::get_lg_dir(const char **dirp);
</pre></b>
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<b>Description: DbEnv::set_lg_dir</b>
<p>The path of a directory to be used as the location of logging files.
Log files created by the Log Manager subsystem will be created in this
directory.</p>
<p>If no logging directory is specified, log files are created in the
environment home directory.   See <a href="../ref/env/naming.html">Berkeley DB File Naming</a> for more information.</p>
<p>For the greatest degree of recoverability from system or application
failure, database files and log files should be located on separate
physical devices.</p>
<p>The database environment's logging directory may also be configured using the
environment's <a href="../ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file.  The syntax of the entry in that
file is a single line with the string "set_lg_dir", one or more whitespace
characters, and the directory name.
Because the <a href="../ref/env/db_config.html#DB_CONFIG">DB_CONFIG</a> file is read when the database environment
is opened, it will silently overrule configuration done before that
time.</p>
<p>The DbEnv::set_lg_dir method configures operations performed using the specified
<a href="../api_cxx/env_class.html">DbEnv</a> handle, not all operations performed on the underlying
database environment.</p>
<p>The DbEnv::set_lg_dir method may not be called after the <a href="../api_cxx/env_open.html">DbEnv::open</a> method is
called.
If the database environment already exists when
<a href="../api_cxx/env_open.html">DbEnv::open</a> is called, the information specified to DbEnv::set_lg_dir
must be consistent with the existing environment or corruption can
occur.</p>
<p>The DbEnv::set_lg_dir method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
 <b>dir</b><ul compact><li>The <b>dir</b> parameter is the directory used to store the logging files.</ul>
<p>When using a Unicode build on Windows (the default), the <b>dir</b>
argument will be interpreted as a UTF-8 string, which is equivalent to
ASCII for Latin characters.</p>
<br>
<br><b>Errors</b>
<p>The DbEnv::set_lg_dir method
may fail and throw
<a href="../api_cxx/except_class.html">DbException</a>,
encapsulating one of the following non-zero errors, or return one of
the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>If the method was called after <a href="../api_cxx/env_open.html">DbEnv::open</a> was called; or if an
invalid flag value or parameter was specified.</ul>
<br>
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<b>Description: DbEnv::get_lg_dir</b>
<p>The DbEnv::get_lg_dir method returns the log directory.</p>
<p>The DbEnv::get_lg_dir method may be called at any time during the life of the
application.</p>
<p>The DbEnv::get_lg_dir method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
 <b>dirp</b><ul compact><li>The DbEnv::get_lg_dir method returns a reference to the
log directory in <b>dirp</b>.</ul>
<br>
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<br><b>Class</b>
<a href="../api_cxx/env_class.html">DbEnv</a>, <a href="../api_cxx/logc_class.html">DbLogc</a>, <a href="../api_cxx/lsn_class.html">DbLsn</a>
<br><b>See Also</b>
<a href="../api_cxx/log_list.html">Logging Subsystem and Related Methods</a>
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